Swiss, German and French catholic bishops have warned of the risks of biotechnology and called on politicians to respect the dignity of life.
At a press conference in Basel the bishops of Freiburg, Basel and Strasbourg have asked politicians, scientists and economists to be more alert to the dangers involved in biotechnology and biomedicine.
Oskar Saier from Freiburg, Joseph Doré from Strasbourg and Kurt Koch from Basel described cloning as "downgrading human life" and accused scientists of using the technology to provide a "warehouse for spare parts".
"The artificial production and use of human embryos for research can never be justified ethically," their common statement said.
The bishops also emphasised that the same issues applied to obtaining embryonic cells, even if they were to be used in the treatment of hereditary diseases.
They also called for discussions to determine where the boundaries of justifiable research lie.
Bishop Saier from Freiburg said that not all research was justifiable and emphasised that not all methods, even if needed for treating ill patients, were ethical.
swissinfo with agencies